a. Field of the Invention
The instant invention relates to localization systems that measure position utilizing localization fields. In particular, the instant invention relates to a system and method to account for inhomogeneity of the localization field.
b. Background Art
It is well known to generate heart chamber geometry in preparation for cardiac diagnostic or therapeutic procedures. Often, a mapping catheter is introduced into the heart chamber of interest and moved around within the heart chamber, either randomly, pseudo-randomly, or according to one or more preset patterns. The three-dimensional coordinates are measured using a localization system (sometimes also referred to as a “mapping system,” “navigation system,” or “positional feedback system”). The localization system measures the coordinates of the mapping catheter within a localization field, typically by relating a characteristic of the localization field, such as a voltage, experienced by the mapping catheter to a location of the catheter within the field. A similar process may be used to measure the position of any object, such as an ablation catheter or other medical device, within the localization field.
It is known, however, that the localization field may not be homogeneous. That is, as an object moves within the localization field, there may not be a constant relationship between the characteristic and the position of the object within the field. These inhomogeneities potentially reduce the precision and accuracy of the position measurements made by the localization system.